* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- * Boston, MA 02111-1307, USA.
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#include "config.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
-#ifdef HAVE_UNISTD_H
-#include <unistd.h>
-#endif
#ifdef HAVE_MMAP
#include <sys/mman.h>
#endif
#include "glibconfig.h"
+#ifdef G_OS_UNIX
+#include <unistd.h>
+#endif
+
#ifdef G_OS_WIN32
#include <windows.h>
#include <io.h>
+#undef fstat
#define fstat(a,b) _fstati64(a,b)
+#undef stat
#define stat _stati64
+#ifndef S_ISREG
+#define S_ISREG(m) (((m) & _S_IFMT) == _S_IFREG)
+#endif
+
#endif
#include "gconvert.h"
#include "gstdio.h"
#include "gstrfuncs.h"
#include "gatomic.h"
-#include "gbufferprivate.h"
#include "glibintl.h"
#define MAP_FAILED ((void *) -1)
#endif
-struct _GMappedFile
+/**
+ * GMappedFile:
+ *
+ * The #GMappedFile represents a file mapping created with
+ * g_mapped_file_new(). It has only private members and should
+ * not be accessed directly.
+ */
+
+struct _GMappedFile
{
gchar *contents;
gsize length;
#endif
};
-/* Make sure the layout of GMappedFile is the same as GBuffer's */
-G_STATIC_ASSERT (G_STRUCT_OFFSET (GMappedFile, contents) ==
- G_STRUCT_OFFSET (GBuffer, data));
-G_STATIC_ASSERT (G_STRUCT_OFFSET (GMappedFile, length) ==
- G_STRUCT_OFFSET (GBuffer, size));
-G_STATIC_ASSERT (G_STRUCT_OFFSET (GMappedFile, ref_count) ==
- G_STRUCT_OFFSET (GBuffer, ref_count));
-G_STATIC_ASSERT (G_STRUCT_OFFSET (GMappedFile, free_func) ==
- G_STRUCT_OFFSET (GBuffer, free_func));
-
static void
g_mapped_file_destroy (GMappedFile *file)
{
g_slice_free (GMappedFile, file);
}
-/**
- * g_mapped_file_new:
- * @filename: The path of the file to load, in the GLib filename encoding
- * @writable: whether the mapping should be writable
- * @error: return location for a #GError, or %NULL
- *
- * Maps a file into memory. On UNIX, this is using the mmap() function.
- *
- * If @writable is %TRUE, the mapped buffer may be modified, otherwise
- * it is an error to modify the mapped buffer. Modifications to the buffer
- * are not visible to other processes mapping the same file, and are not
- * written back to the file.
- *
- * Note that modifications of the underlying file might affect the contents
- * of the #GMappedFile. Therefore, mapping should only be used if the file
- * will not be modified, or if all modifications of the file are done
- * atomically (e.g. using g_file_set_contents()).
- *
- * Return value: a newly allocated #GMappedFile which must be unref'd
- * with g_mapped_file_unref(), or %NULL if the mapping failed.
- *
- * Since: 2.8
- */
-GMappedFile *
-g_mapped_file_new (const gchar *filename,
- gboolean writable,
- GError **error)
+static GMappedFile*
+mapped_file_new_from_fd (int fd,
+ gboolean writable,
+ const gchar *filename,
+ GError **error)
{
GMappedFile *file;
- int fd;
struct stat st;
- g_return_val_if_fail (filename != NULL, NULL);
- g_return_val_if_fail (!error || *error == NULL, NULL);
-
- fd = g_open (filename, (writable ? O_RDWR : O_RDONLY) | _O_BINARY, 0);
- if (fd == -1)
- {
- int save_errno = errno;
- gchar *display_filename = g_filename_display_name (filename);
-
- g_set_error (error,
- G_FILE_ERROR,
- g_file_error_from_errno (save_errno),
- _("Failed to open file '%s': open() failed: %s"),
- display_filename,
- g_strerror (save_errno));
- g_free (display_filename);
- return NULL;
- }
-
file = g_slice_new0 (GMappedFile);
file->ref_count = 1;
file->free_func = g_mapped_file_destroy;
if (fstat (fd, &st) == -1)
{
int save_errno = errno;
- gchar *display_filename = g_filename_display_name (filename);
+ gchar *display_filename = filename ? g_filename_display_name (filename) : NULL;
g_set_error (error,
G_FILE_ERROR,
g_file_error_from_errno (save_errno),
- _("Failed to get attributes of file '%s': fstat() failed: %s"),
- display_filename,
+ _("Failed to get attributes of file '%s%s%s%s': fstat() failed: %s"),
+ display_filename ? display_filename : "fd",
+ display_filename ? "' " : "",
+ display_filename ? display_filename : "",
+ display_filename ? "'" : "",
g_strerror (save_errno));
g_free (display_filename);
goto out;
}
- if (st.st_size == 0)
+ /* mmap() on size 0 will fail with EINVAL, so we avoid calling mmap()
+ * in that case -- but only if we have a regular file; we still want
+ * attempts to mmap a character device to fail, for example.
+ */
+ if (st.st_size == 0 && S_ISREG (st.st_mode))
{
file->length = 0;
file->contents = NULL;
- close (fd);
return file;
}
if (file->contents == MAP_FAILED)
{
int save_errno = errno;
- gchar *display_filename = g_filename_display_name (filename);
-
+ gchar *display_filename = filename ? g_filename_display_name (filename) : NULL;
+
g_set_error (error,
G_FILE_ERROR,
g_file_error_from_errno (save_errno),
- _("Failed to map file '%s': mmap() failed: %s"),
- display_filename,
+ _("Failed to map %s%s%s%s: mmap() failed: %s"),
+ display_filename ? display_filename : "fd",
+ display_filename ? "' " : "",
+ display_filename ? display_filename : "",
+ display_filename ? "'" : "",
g_strerror (save_errno));
g_free (display_filename);
goto out;
}
- close (fd);
return file;
out:
- close (fd);
g_slice_free (GMappedFile, file);
return NULL;
}
/**
+ * g_mapped_file_new:
+ * @filename: The path of the file to load, in the GLib filename encoding
+ * @writable: whether the mapping should be writable
+ * @error: return location for a #GError, or %NULL
+ *
+ * Maps a file into memory. On UNIX, this is using the mmap() function.
+ *
+ * If @writable is %TRUE, the mapped buffer may be modified, otherwise
+ * it is an error to modify the mapped buffer. Modifications to the buffer
+ * are not visible to other processes mapping the same file, and are not
+ * written back to the file.
+ *
+ * Note that modifications of the underlying file might affect the contents
+ * of the #GMappedFile. Therefore, mapping should only be used if the file
+ * will not be modified, or if all modifications of the file are done
+ * atomically (e.g. using g_file_set_contents()).
+ *
+ * If @filename is the name of an empty, regular file, the function
+ * will successfully return an empty #GMappedFile. In other cases of
+ * size 0 (e.g. device files such as /dev/null), @error will be set
+ * to the #GFileError value #G_FILE_ERROR_INVAL.
+ *
+ * Returns: a newly allocated #GMappedFile which must be unref'd
+ * with g_mapped_file_unref(), or %NULL if the mapping failed.
+ *
+ * Since: 2.8
+ */
+GMappedFile *
+g_mapped_file_new (const gchar *filename,
+ gboolean writable,
+ GError **error)
+{
+ GMappedFile *file;
+ int fd;
+
+ g_return_val_if_fail (filename != NULL, NULL);
+ g_return_val_if_fail (!error || *error == NULL, NULL);
+
+ fd = g_open (filename, (writable ? O_RDWR : O_RDONLY) | _O_BINARY, 0);
+ if (fd == -1)
+ {
+ int save_errno = errno;
+ gchar *display_filename = g_filename_display_name (filename);
+
+ g_set_error (error,
+ G_FILE_ERROR,
+ g_file_error_from_errno (save_errno),
+ _("Failed to open file '%s': open() failed: %s"),
+ display_filename,
+ g_strerror (save_errno));
+ g_free (display_filename);
+ return NULL;
+ }
+
+ file = mapped_file_new_from_fd (fd, writable, filename, error);
+
+ close (fd);
+
+ return file;
+}
+
+
+/**
+ * g_mapped_file_new_from_fd:
+ * @fd: The file descriptor of the file to load
+ * @writable: whether the mapping should be writable
+ * @error: return location for a #GError, or %NULL
+ *
+ * Maps a file into memory. On UNIX, this is using the mmap() function.
+ *
+ * If @writable is %TRUE, the mapped buffer may be modified, otherwise
+ * it is an error to modify the mapped buffer. Modifications to the buffer
+ * are not visible to other processes mapping the same file, and are not
+ * written back to the file.
+ *
+ * Note that modifications of the underlying file might affect the contents
+ * of the #GMappedFile. Therefore, mapping should only be used if the file
+ * will not be modified, or if all modifications of the file are done
+ * atomically (e.g. using g_file_set_contents()).
+ *
+ * Returns: a newly allocated #GMappedFile which must be unref'd
+ * with g_mapped_file_unref(), or %NULL if the mapping failed.
+ *
+ * Since: 2.32
+ */
+GMappedFile *
+g_mapped_file_new_from_fd (gint fd,
+ gboolean writable,
+ GError **error)
+{
+ return mapped_file_new_from_fd (fd, writable, NULL, error);
+}
+
+/**
* g_mapped_file_get_length:
* @file: a #GMappedFile
*
* Increments the reference count of @file by one. It is safe to call
* this function from any thread.
*
- * Return value: the passed in #GMappedFile.
+ * Returns: the passed in #GMappedFile.
*
* Since: 2.22
**/
if (g_atomic_int_dec_and_test (&file->ref_count))
g_mapped_file_destroy (file);
}
+
+/**
+ * g_mapped_file_get_bytes:
+ * @file: a #GMappedFile
+ *
+ * Creates a new #GBytes which references the data mapped from @file.
+ * The mapped contents of the file must not be modified after creating this
+ * bytes object, because a #GBytes should be immutable.
+ *
+ * Returns: (transfer full): A newly allocated #GBytes referencing data
+ * from @file
+ *
+ * Since: 2.34
+ **/
+GBytes *
+g_mapped_file_get_bytes (GMappedFile *file)
+{
+ g_return_val_if_fail (file != NULL, NULL);
+
+ return g_bytes_new_with_free_func (file->contents,
+ file->length,
+ (GDestroyNotify) g_mapped_file_unref,
+ g_mapped_file_ref (file));
+}
projects / platform / upstream / glib.git / blobdiff